package com.atguigu.gulimall.product.service.impl;

import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;
import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryBrandRelationService;
import com.atguigu.gulimall.product.service.CategoryService;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.*;
import java.util.stream.Collectors;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Autowired
    private CategoryBrandRelationService categoryBrandRelationService;

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        // 1、查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);

        // 2、组装成分子的树形结构
        // 2.1、找到所有的一级分类
        List<CategoryEntity> level1Menus = entities.stream().filter((categoryEntity) -> categoryEntity.getParentCid() == 0)
                .map((menu -> {
                    menu.setChildren(getChildren(menu, entities));
                    return menu;
                }))
                .sorted(Comparator.comparingInt(menu -> (menu.getSort() == null ? 0 : menu.getSort())))
                .collect(Collectors.toList());
        return level1Menus;
    }

    @Override
    public void removeMenuById(List<Long> asList) {
        // TODO 查当前删除的菜单，是否被别的地方引用
        // 逻辑删除
        baseMapper.deleteBatchIds(asList);
    }

    /**
     * @Description: 递归查找所有菜单的子菜单
     * @Param: [root, all]
     * @return: java.util.List<com.atguigu.gulimall.product.entity.CategoryEntity>
     * @Author: xiaoxiaokui
     * @Date: 2020/6/2
     */
    private List<CategoryEntity> getChildren(CategoryEntity root, List<CategoryEntity> all) {
        List<CategoryEntity> children = all.stream().filter(categoryEntity -> categoryEntity.getParentCid().equals(root.getCatId()))
                .map(categoryEntity -> {
                    // 1、找到子菜单
                    categoryEntity.setChildren(getChildren(categoryEntity, all));
                    return categoryEntity;
                })
                // 2、菜单的排序
                .sorted(Comparator.comparingInt(menu -> (menu.getSort() == null ? 0 : menu.getSort())))
                .collect(Collectors.toList());
        return children;
    }

    @Override
    public Long[] findCatelogPath(Long catelogId) {
        List<Long> paths = new ArrayList<>();
        List<Long> parentPath = findParentPath(catelogId, paths);

        Collections.reverse(parentPath);
        return (Long[]) parentPath.toArray(new Long[parentPath.size()]);
    }

    /**
     * 级联更新所有关联的数据
     * @param category
     */
    @Transactional
    @Override
    public void updateCascade(CategoryEntity category) {
        this.updateById(category);
        categoryBrandRelationService.updateCategory(category.getCatId(), category.getName());
    }

    private List<Long> findParentPath(Long catelogId, List<Long> paths) {
        // 1、收集当前节点id
        paths.add(catelogId);
        CategoryEntity byIdE = this.getById(catelogId);
        if (byIdE.getParentCid() != 0) {
            findParentPath(byIdE.getParentCid(), paths);
        }
        return paths;
    }

}